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The Virtual Lab Experiment
Some colleges use computer simulations to expand science offerings online
By DAN CARNEVALE
When Afton-Dawn Ellison messes up a chemistry experiment, the smoke from the
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explosion and the shattering glass don't distress her. She
simply clicks her computer mouse a few times and starts
over.
2 Ways to Teach Laboratory
Ms. Ellison's laboratory section relies on computer
simulations, rather than on actual chemicals and glassware.
It is part of a distance-education degree program at
Brigham Young University, where Ms. Ellison is a student.
The simulation, called Virtual ChemLab, allows students to conduct experiments safely
while studying at home.
Science
Learning on the computer simulations can also be fun, Ms. Ellison says. The Virtual
ChemLab plays sound and visual effects as chemicals react, whether subtly or with a bang.
"I really liked blowing stuff up in the virtual lab," she says. "In the virtual lab you can try
anything you want, and it's OK."
The Virtual ChemLab was developed by Brian F. Woodfield, an assistant professor of
chemistry at Brigham Young. He says students get hands-on chemistry experience without
actually putting their hands on any dangerous chemicals. The virtual lab also allows
students to experiment on their own, instead of having to follow instructions rigidly, as
they would in a traditional lab.
Only a few years ago, professors saw no way to offer hard-science labs at a distance. But
now a handful of institutions around the country have begun experimenting with the idea.
Through computer animation and creative adaptation, students are able to do such things as
conduct biology research online or perform chemistry experiments in their kitchens. And
some college officials say the labs are rigorous enough that students who take them can
earn college credit.
A number of virtual labs received financial backing from the U.S. Education Department's
Fund for the Improvement of Postsecondary Education.
Creating Labs Is Costly
The labs have limitations, however. Most biology professors still say that the experience of
dissecting a frog while gagging on the stench of formaldehyde simply can't be replicated
online. And it's expensive and time-consuming to develop a virtual lab that includes all the
possible variables that students can encounter in a real lab. Meanwhile, accreditors are
perplexed over how to evaluate a lab that has no equipment.
Some scientists worry that students who only have virtual-lab experience will not acquire
the hands-on familiarity they should get out of science labs. Jerry Bell, senior scientist at
the American Chemical Society, says students' experience will be limited to what
professors put in the computer program. But in a real lab, a student can mess up an
experiment in any number of ways a professor would never anticipate.
"I'm not convinced," Mr. Bell says. "When it's only on a computer, I'm not really certain
they'll learn anything."
Better Than Reality?
Some professors are slowly integrating virtual labs into traditional degree programs. Some
of the online labs help students who are not science majors fulfill the laboratory
requirements for their degrees. And other online labs give science majors the opportunity
to use equipment virtually that their institutions do not have. But students generally can't
complete an entire major in the hard sciences with only virtual-lab experience.
Mr. Woodfield, who developed the BYU Virtual ChemLab, says the online experience is
just about as good as the real thing. The Virtual Chemlab, which allows students to
complete assignments on a computer and submit their reports online, is available for labs
in organic synthesis, inorganic qualitative analysis, and quantum mechanics. Mr.
Woodfield says the inorganic-chemistry version of the software can simulate 10 million
billion outcomes, depending on what chemicals are mixed and how the student conducts
the experiment.
Mr. Woodfield says the online lab allows students to experiment more than they would be
able to in a real lab. Because of time and safety constraints, students usually cannot freely
experiment with real chemicals. The results could be disastrous, he says. Instead, he says,
"the students end up doing a lot of cookbooking --they have detailed instructions, they do
the work, and they're happy with the results."
On the other hand, the computer simulations in the Virtual ChemLab encourage students to
experiment and have some fun. "We try to minimize the technical aspects and try to
maximize the open-endedness and discovery aspects," he says. "We're teaching them that
creative process, that problem-solving process."
The software presents 2,500 photographs and 220 video clips of real lab results. Because
different combinations of chemicals can have similar results, he says, the same
photographs and videos can sometimes be used to represent the outcomes of different
experiments. "Muck looks like muck, so we show them muck," Mr. Woodfield says.
In a new online microbiology lab offered by the University of Texas Medical Branch in
Galveston, students don't have to worry about ruining bacterial cultures --they are part of a
computer simulation, says Vicki S. Freeman, chairwoman of clinical laboratory sciences at
the Medical Branch's School of Allied Health Sciences.
"We're actually able to give them more variables than we would in a clinical laboratory,"
Ms. Freeman says. "Virtually, we can re-create any circumstances we want."
In a real lab, creating bacterial cultures is expensive and time-consuming. When students
are working with a real gonorrhea culture, for instance, professors usually must monitor
them closely to make sure they don't start the wrong procedure and waste the valuable
material. Students don't have to worry about that online.
The U.S. Department of Education financed the lab with a $1.1-million grant.
Virtual-Lab Partners
Some professors say that essential components of a lab experience are lab partners and
instructors. Gerald W. Meisner, a physics professor at the University of North Carolina at
Greensboro, is developing an online physics lab that will provide not only computer
simulations of experiments, but also virtual professors and virtual lab mates. A trial version
will be available in the spring.
The Education Department is financing the creation of the virtual physics lab with a
$1.8-million grant. The lab, called Learn Anytime Anywhere Physics, will include graphic
animations of instruments as students go online to test principles of mechanics, waves,
electricity, magnetism, and optics. A virtual professor will ask questions as a student
conducts experiments. How the student answers will let the computer program know how
well the student is grasping the physics concepts.
Accompanying the distance student in the virtual lab will be virtual lab partners --phantom
students who will cooperate with the distance student on the lab work. But the student will
not know whether the lab partners are giving good or bad advice, just as in a real
laboratory experience.
Not all distance-education labs use computer-simulated virtual reality. Two science
professors have cooked up a way for students to fulfill their science-lab requirements
online by turning their home kitchens into chemistry labs. Instead of using test tubes and
beakers, the students make do with measuring cups and saucepans.
Doris R. Kimbrough, an associate chemistry professor at the University of Colorado at
Denver, and Jimmy Reeves, an associate professor of chemistry at the University of North
Carolina at Wilmington, developed the course. It is offered to on-campus students at
Denver through the University of Colorado, and --through the University of North Carolina
--to students who attend Cape Fear Community College, in Wilmington. The program
helps nonscience majors and first-semester students get a taste of chemistry while working
comfortably in their own kitchens.
The lab was financed by a $400,000 grant from the Department of Education. This is the
third year that the professors have been offering the online chemistry course. So far,
nobody's house has blown up or burned down. "All my students still have all their fingers
and toes," Ms. Kimbrough says. "It's going well."
The professors say the experiments are safe, and that most of the material can be purchased
from the local grocery store or a Wal-Mart.
In one experiment, the student sticks a pin into a nut and ignites the nut with a match. The
oil in the nut begins to burn. The student heats water with the flame from the nut and
measures the rise in the water's temperature. Then the student uses the temperature
difference to calculate how many calories the nut contained.
Ms. Kimbrough says students enjoy the mix of experiments they get to do. "We've gotten a
lot of mileage out of baking soda and vinegar," she says. "It's a cute reaction because it
gives off gas."
While students have fun making smoke and fire, Mr. Reeves says, they are also learning at
least as much as they would learn in an on-campus chemistry lab. Online students
outperformed on-campus students on the final exams and on the in-lab practical exams that
Mr. Reeves gave on the campus to some of the distance-education students to see how they
stacked up against the campus students.
Jon Branham completed the distance chemistry course in the fall while enrolled at Cape
Fear Community College. He says the lab work helped him grasp the material better than
he had in previous chemistry courses because the experiments involved household items,
like nuts and vinegar. "I understood things a lot better because it's more common," Mr.
Branham says. "All of the experiments took place on my stove."
Mixed Bag With CD-ROM's
Other experiments with virtual laboratories did not go as well, however. Coastline
Community College, for example, cut short a project to create a computerized version of a
biology lab. Laurie Melby, director of production at Coastline, says the college planned to
put together a CD-ROM that covered 12 topics of a virtual biology lab.
But the project's creators found that including all the variables found in a traditional lab
was much more difficult and much more costly than they had anticipated. In the end, the
CD-ROM covers only one topic as a supplement to a traditional lab. The college, in
California, spent about $184,000 from an Education Department grant to pay for the
project.
The CD-ROM lets students play a game that focuses on research methods by having
students investigate a lake where fish are sick and dying. The students find out what's
wrong by analyzing the lake's conditions and other variables, such as the time of day, time
of year, oxygen rate, and amount of toxins in the water. Each time students play the game,
they'll face a different combination of variables.
But including so many variables and animating the game to make it enjoyable took time
and money.
"The more interesting you want that to be with the student, the more complicated you get
with programming and animating," Ms. Melby says. "There were a lot of complications
that we ran into along the way --a lot of difficulties that were not foreseen."
One acid test for virtual labs will be how they are judged by accrediting agencies. Olive M.
Kimball is the chief executive officer of the National Accrediting Agency for Clinical
Laboratory Sciences, which evaluates more than 500 collegiate laboratory programs in the
country. She says she is not familiar with any virtual labs. But she says accreditors will
have to focus on what students get out of the lab instead of on easily quantified issues like
how much equipment the lab has.
Online science labs are a welcome development because they allow distance-education
students to gain some laboratory experience, Ms. Kimball says. But she is suspicious of
whether students can get adequate hands-on experience with a virtual lab, in which they
never really touch a beaker or culture a bacteria. "I'm sure that many of our program
directors are concerned about it," she says
John E. Penick, president-elect of the National Science Teachers Association, an
organization made up of school and college science teachers, says that the virtual labs
serve a good purpose, but that ideally they should be used in conjunction with, or as
supplements to, traditional labs.
"It's wonderful stuff, but it should be mixed with reality," says Mr. Penick, who is also
head of the department of mathematics, science, and technology education at North
Carolina State University. "I'd prefer it not be the only online lab experience, but my
feeling is a simulated experience is better than none."
2 WAYS TO TEACH LABORATORY SCIENCE
Online laboratory courses try to teach the same skills as those taught in actual laboratories.
Here is how four institutions handle laboratory instruction in both types of courses:
Brigham Young University
Course: Advanced chemistry lab
Traditional: Students follow a specific procedure for mixing cations, or positively charged
ions, to see how they react. The experiments can take weeks. Safety is an issue because
some cations are toxic.
Online: Students use a computer simulation that allows them to experiment with virtual
cations without following specific procedures. Students may safely use virtual
representations of toxic cations, such as mercury, and experiments that normally take
weeks are finished in minutes.
University of Colorado at Denver
Course: Introductory chemistry lab
Traditional: Students burn nuts with matches to heat cups of water. As the water warms,
the students measure the rise in temperature to calculate the number of calories in each nut.
Online: In their own kitchens, students burn nuts with matches to calculate the number of
calories.
University of North Carolina at Greensboro
Course: Advanced physics lab
Traditional: Students work with lab partners to measure the speeds of remote-controlled
cars and plot the results on graphs.
Online: Students use computer simulations of remote-controlled cars. While students
conduct the experiments, the software acts as a virtual lab partner and offers good and bad
advice to the students to test their problem-solving skills.
University of Texas Medical Branch
Course: Advanced microbiology lab
Traditional: Students on the Galveston campus combine bacterial cultures with various
chemicals to examine reactions. The experiments can take weeks, and the students usually
must avoid certain procedures that could ruin expensive cultures.
Online: Students run experiments with virtual bacterial cultures by telling a computer what
chemicals to add. Reaction times are cut to minutes, letting students spend more time
experimenting.
SOURCE: Chronicle reporting
http://chronicle.com
Section: Information Technology
Volume 49, Issue 21, Page A30
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